Associations between napping patterns and nocturnal sleep among student-athletes: A daily actigraphy-based study

Although daytime napping is common among student-athletes to support recovery and performance, naps may interfere with nocturnal sleep depending on timing and duration. This study examined same-day associations between napping patterns and nocturnal sleep in student-athletes using daily actigraphy. Seven consecutive days of actigraphy and diary data were analyzed from 61 student-athletes (42.6% male; mean age, 19.5 years) who napped at least once. Multilevel linear regression models examined associations between nap variables (occurrence, start time, end time, duration, and position) and nocturnal sleep variables (bedtime, wake-up time, total sleep time [TST], and sleep efficiency). Models were adjusted for sex, age, early morning training, night training, caffeine intake after 5:00 p.m., and electronic device use after lights out. Later nap timing and longer nap duration were associated with less favorable nocturnal sleep. Compared with naps before noon, naps starting after 5:00 p.m. were associated with bedtimes 42 minutes later (b = 0.697, p = 0.03), and naps ending after 5:00 p.m. with bedtimes 47 minutes later (b = 0.777, p = 0.02). Compared with naps lasting 1–30 minutes, naps lasting ≥61 minutes were associated with 28.2 minutes shorter TST (b = −28.184, p = 0.04) and 3.8 percentage points lower sleep efficiency (b = −3.775, p < 0.01). These findings indicate that later and longer naps are associated with less favorable nocturnal sleep. Avoiding naps after 5:00 p.m. and limiting nap duration to 60 minutes or less may help student-athletes maintain nocturnal sleep while using naps for recovery.